Many consumer products, such as health and personal care products, are manufactured and packaged in solid, compacted form. The solid, compacted product form has several advantages over other product forms, such as relative ease of manufactures and durability in shipment and convenience in storing for retailers and consumers alike. The tablet solid form is particularly well-suited for over-the-counter prescription pharmaceutical, and nutritional products that are to be administered orally, because virtually any pharmaceutically-active medicament is capable of being granulated and prepared in powdered form without affecting its medicinal effectiveness. Moreover, after being swallowed, the tablets quickly disintegrate within the acidic environment of the stomach, and the active medicament within the tablet is readily digested and absorbed into the blood stream.
However, in certain situations it would be beneficial if the tablet would disintegrate in the mouth so that the active pharmaceutical could be delivered to the blood stream of a patient without the necessity of swallowing the tablet. For example, children and advanced geriatric patients (those over 80 years old) often have difficulty swallowing pills, and a tablet that dissolves or rapidly disintegrates in the mouth would provide a convenient and effective solid form delivery system for such patients. Additionally, a tablet that dissolves, or disintegrates, in the mouth would be helpful for mentally disabled individuals who require treatment with pharmaceuticals, but refuse to swallow tablets.
Yet another situation where oral disintegration would be helpful is where water may not be readily available to assist in swallowing the tablet, such as when a person is traveling in an automobile or under certain working conditions.
Unfortunately, most tablets do not readily dissolve in the mouth, but instead disintegrate in a slow and uneven fashion, so that if the tablet is not swallowed, then a dosage significantly below the therapeutically effective level will be delivered to the bloodstream. This is particularly serious when a pharmaceutical tablet is administered to treat a bacterial disease, and the refusal of a patient to swallow the tablet results in a sub-therapeutically effective amount of an antibiotic being delivered to the bloodstream, allowing the bacteria to develop resistance to the antibiotic. Given the forgoing there is a continuing need for solid form pharmaceutical preparations that rapidly disintegrate. Particularly needed are tablet compositions that readily disintegrate in the mouth, and thereby eliminate the need for the tablet to be swallowed.
The present invention includes a calcium metasilicate having an aspect ratio (average major axial diameter/average minor axial diameter) of from about 1:1 to about 2.5:1, and an oil absorption of from about 20 ml/100 g to about 220 ml/100 g.
The invention also includes a method of forming a dehydrated calcium metasilicate comprising the steps of: providing a calcium source and a silica source, at a molar ratio of calcium in the calcium source to silica in the silica source is from about 0.75 to about 1.3, preferably from about 0.95 to about 1.05; mixing the calcium source with the silica source to form a homogeneous mixture; and heating the homogenous mixture to form dehydrated calcium metasilicate.
The invention also includes pharmaceutical, food, agricultural and cosmetic products including the calcium metasilicate prepared according to the present invention.